Death Investigations & Postmortem Toxicology

How can a forensic toxicologist assist with a death investigation?

A forensic toxicologist evaluates what was tested, what was detected, how the testing was performed, and what the findings may mean in the context of the death. The review can identify missing information, analytical limitations, potential drug effects, and alternative scientific explanations.

Dr. Javed's role is independent scientific consultation. Her review can inform a death investigation but does not replace an autopsy or the responsibilities of the medical examiner, coroner, or other authorized death certifier.

Does finding a drug prove that it caused the death?

No. Detecting a substance establishes its presence within the capabilities of the test; it does not, by itself, establish that the substance caused or contributed to death.

Interpretation requires consideration of the concentration, specimen type and collection site, other substances, medical conditions, treatment before death, and the investigative and autopsy findings. A drug may be incidental, contributory, or central to the death, depending on the evidence.

What is postmortem redistribution?

Postmortem redistribution refers to changes in drug concentrations after death as substances move between tissues, organs, and blood. The extent of these changes depends on the substance, sampling location, time since death, and other circumstances.

A concentration measured after death should not automatically be treated as the concentration that was present during life. Redistribution must be considered, but it does not make every postmortem result unusable or prevent a supported interpretation.

How are fentanyl and other synthetic opioids evaluated?

A review considers whether the testing method included the relevant opioid and its metabolites, the reliability of the identification and measurement, and the specimen and case circumstances. Fentanyl and some other synthetic opioids can suppress breathing, but their detection alone does not establish the role they played in a particular death.

Relevant considerations include other drugs or alcohol, treatment before death, medical conditions, and the available history of opioid use. A single concentration should not be treated as a universal fatal threshold.

What does combined drug toxicity mean?

Combined drug toxicity describes a situation in which more than one substance contributes to harmful or fatal effects. For example, opioids, benzodiazepines, and alcohol can have combined effects that increase the risk of respiratory depression.

The presence of several substances does not automatically mean that all contributed to death. Each substance and any plausible interaction must be assessed in the context of the full record; the combined effect cannot be determined simply by adding the reported concentrations.

Can published therapeutic, toxic, or fatal ranges settle the interpretation?

No. Published ranges provide context, not a stand-alone answer for an individual death. Reported ranges may overlap, and the underlying studies may involve different specimens, circumstances, and populations.

Tolerance, other substances, underlying disease, specimen differences, and postmortem changes can affect interpretation. A result within a reported fatal range does not by itself prove causation, and a result below such a range does not necessarily exclude a contribution to death. Tolerance cannot be assigned a precise numerical value from a postmortem result alone.

Why do specimen type and collection site matter?

Blood, urine, vitreous fluid, and tissue samples provide different information. Even blood collected from different anatomical sites may yield different drug concentrations, particularly when postmortem redistribution is relevant.

The review should establish what specimen was tested, where and when it was collected, and how it was preserved and stored. Results from different specimens should not be treated as interchangeable. Samples collected during medical treatment before death may provide additional context when available.

Does a negative toxicology report rule out a drug-related death?

Not necessarily. A negative result means that the substances covered by the method were not detected above the applicable reporting limits in the specimens tested. It does not establish that every possible drug or toxic substance was excluded.

The testing scope, detection limits, specimen availability, stability, and timing all matter. Additional testing may sometimes be useful, but its suitability depends on the scientific question and whether appropriate specimens remain available.

What records are useful for a postmortem toxicology review?

Depending on the matter, relevant materials may include:

• Complete toxicology reports, including specimen types, collection sites, units, reporting limits, and the scope of testing.
• Available laboratory documentation supporting identification, quantitation, quality control, and any amended results.
• Autopsy and pathology reports, the death certificate, and relevant medical history.
• Scene and investigative records, medication information, and available witness accounts.
• Emergency response and hospital records, including medications administered and any specimens collected before death.
• Specimen collection, preservation, storage, and chain-of-custody records, along with any prior expert reports.

Missing records or unavailable specimens may limit the questions that can be answered. An independent review does not guarantee a different conclusion from the original investigation.